Valve announces that Counter-Strike: Global Offensive is now available on Steam, offering the Windows and OS X editions of the new installment in the teamplay shooter series which will also come to consoles over the next day or so. Here's word:

Valve, creators of best-selling game franchises (such as Half-Life and Team Fortress) and leading technologies (such as Steam and Source), today announced Counter-Strike: Global Offensive is now available via Steam, with the North American PSN launch and worldwide Xbox launch happening later tonight and tomorrow morning. .

CS: GO expands on the classic team-based action gameplay that Counter-Strike pioneered. Featuring an arsenal of over 45 weapons, loads of maps, new game modes, new visuals, leaderboards and over 165 Steam Achievements.